Float type drain trap

Abstract

The present invention provided a float type drain trap capable of preventing penetration of foreign matters into the pilot valve to eliminate troubles caused with penetration of foreign matters, furnishing the pilot valve operation with stability and function of snap action, and reducing the bore diameter of the pilot valve to make the float as small as possible. The pilot valve mechanism is constructed by comprising a pilot valve 7 , disposed in part of the pilot chamber 8 and putting the pilot chamber 8 in communication with the outside of the drain case 1 , an orifice 9 , formed on the upstream side of the pilot valve 7 and putting the pilot chamber 8 in communication with the inside of the drain case 1 , and a microfilter 10 provided on the orifice 9 , and a permanent magnet 11 is provided on said pilot valve 7 , while on said float 6 is provided a permanent magnet 12 for operating the pilot valve 7 in repellence to the permanent magnet 11.

1 . A float type drain trap realized by providing a drain valve for opening/closing the discharge port of a drain case on a piston stored in a cylinder, and also providing a pilot valve mechanism for opening the drain valve by making pilot air pressure act on the piston, to open/close the pilot valve of said pilot valve mechanism with up-down motions of a float disposed on the outside of said cylinder, characterized in that 
 said pilot valve mechanism is constructed by comprising a pilot valve, disposed in part of the pilot chamber and putting the pilot chamber in communication with the outside of the drain case, an orifice, formed on the upstream side of the pilot valve and putting the pilot chamber in communication with the inside of the drain case, and a filter provided on the orifice,    a permanent magnet is provided on said pilot valve, and that    on said float is provided a permanent magnet for operating the pilot valve in repellence to that permanent magnet.